Fossil fuels constitute the largest source of energy supply in the world. Their availability in large quantities, high energy density, and relatively low cost makes fossil fuels the fuel of choice for many applications for both industries and consumers. Nonetheless, an alternative to fossil fuels as an energy source is highly desirable for safety reasons, for environmental reasons, and to reduce the dependence of the industrialized world on oil imported from relatively few oil-producing countries. In spite of these compelling arguments in favor of new energy sources, no economical, safe and readily available fuel has been found to be a viable alternative for fossil fuels, especially in automotive and portable power applications, even though extensive research has been aimed at developing a fuel having the many positive characteristics of gasoline without its drawbacks.
A new, alternative fuel should fulfill several requirements. The cost of the fuel should be competitive with the cost of current energy sources. The fuel should have no undesirable emissions. It should have a high energy density, as gasoline does, to avoid the need for frequent refilling. The fuel should be easy to handle. Preferably, it should be non-flammable and nontoxic, and have a pH as close to 7 as possible. Finally, it should be universally available through a reliable distribution infrastructure that can be readily expanded. There is therefore a need in the art for a fuel having all of the above characteristics.
Current efforts directed to new fuels have not provided a fuel that is cost effective compared to gasoline. Furthermore, the effectiveness of any of the proposed alternatives as a source of energy appears problematic. For example, although hydrogen may be obtained from fossil or non-fossil sources, problems related to handling during transportation and to storage make hydrogen a poor chioce for a consumer-oriented fuel. Other fuels, such as methanol, are toxic and flammable and still require a certain amount of fossil fuel, in the form of either natural gas or carbon monoxide, to be economically produced. Sources of hydrogen such as chemical hydrides, while easy and effective to use, require a recycle loop if it is desired to re-utilize the hydrides, as discussed in U.S. Pat. Nos. 5,804,329 and 6,534,033.
All fossil fuel type reformers require crude oil based liquid fuels and therefore do not alleviate the need for fossil fuels. It is also questionable whether the cost of such reformers may become economical or whether the net “well to wheel” efficiency of such a system may ever match that of a high compression ratio engine. Therefore, it is desirable to provide a fuel that may be used safely within the existing infrastructure, and which at the same time may function as a non-fossil source without causing an increase change in cost at the fuel pump. For example, urea is currently made in very large quantites at a price which can allow it to be competitive with gasoline. It is currently made from hydrogen obtained from natural gas, thereby avoiding the need to import oil. At the same time, the source of hydrogen is flexible, so that non-fossil hydrogen sources may be seamlessly substituted for fossil hydrogen sources to produce urea.